Carbon, activated preparation

Fig. 4.17 Plot of log,o(n/(mmol g ) against logfo (p7p) for the adsorption of benzene at 20°C on a series of progressively activated carbons prepared from sucrose. (Courtesy Dubinin.)...

Typical adsorption isotherms for light hydrocarbons on activated carbon prepared from coconut shells ate shown in Figure 11 (46). The polarizabihties and boiling points of these compounds increase in the order... 

A wide variety of carbon materials has been used in this study, including multi-wall carbon nanotubes (sample MWNT) chemically activated multi-wall carbon nanotubes (sample A-MWNT)16, commercially available vapor grown carbon nanofibers (sample NF) sample NF after chemical activation with K.OH (sample A-NF) commercially pitch-based carbon fiber from Kureha Company (sample CF) commercially available activated carbons AX-21 from Anderson Carbon Co., Maxsorb from Kansai Coke and Chemicals and commercial activated carbon fibers from Osaka Gas Co. (A20) a series of activated carbons prepared from a Spanish anthracite (samples named K.UA) and Subituminous coal (Samples H) by chemical activation with KOH as described by D. Lozano-Castello et al.17 18 activated carbon monoliths (ACM) prepared from different starting powder activated carbons by using a proprietry polymeric binder from Waterlink Sutcliffe Carbons, following the experimental process described in the previous paper13. 

In 2009, Onda et al. studied the catalytic activity of sulfonated activated carbon prepared from active carbon and concentrated sulfuric acid [47]. The hydrolysis was performed under hydrothermal conditions at 423 K in a steel autoclave lined with Teflon. After 24 h of reaction, sulfonated carbon afforded high yield of glucose (40 C-%, i.e., based on the total weight consumption of carbon) and nearly no SO4 elution was observed which clearly indicated that the process was heterogeneously catalyzed. As observed above, under hydrothermal conditions, the glucose yield... 

Budinova, T Petrov, N., Razvigorova, M. et al. (2006) Removal of As(III) from aqueous solution by activated carbons prepared from solvent extracted olive pulp and olive stones. Industrial and Engineering Chemistry Research, 45(6), 1896-901. 

FIGURE 4.4 High-resolution N2 adsorption-desorption isotherms at 77 K (a) normal and (b) semilogarith-mic scale, for three porous carbon materials. Open symbols adsorption full symbols desorption. ACF1 ACF prepared from Nomex aramid fiber by physical activation with C02 [29] AC1 and AC2 activated carbons prepared from Spanish Anthracite by chemical activation with KOH [21]. 

Thermodynamic models analyzed above are applicable to the treatment of results of measurement of characteristics of microporous materials, especially active carbons prepared by pyrolysis of organic materials. 

The main problem in the application of thermodynamic models to the computer treatment of experimental results is that most experimental data are obtained for simple systems (active carbons prepared in conditions close equilibrium), because just such systems are readily available for laboratory studies. 

The author applied some models of systems with regular fluxes to the treatment of data on the adsorption of gases on various active carbons [4]. The steady-state model had been applied to numerous kinds of active carbons prepared in laboratory conditions the correlation between experimental and theoretical results was very good for most treated systems [4]. The nonsteady-state model had been applied to some carbons prepared at various temperatures the correlation of experimental/theoretical results was fair [5]. 

Measurement of adsorption/desorption, percolation, mechanical stability and adhesion characteristics of active carbons prepared in ordinary laboratory conditions and then the application of models of steady-state systems with random fluxes to the complexes of measured parameters. 

Exploratory investigations (Freeman et al., 1991, 1993) of the use of more highly ordered polymeric precursors have shown that there remains considerable scope for the development of novel activated chars from synthetic textile fibres. For example, carbon dioxide breakthrough measurements revealed that activated carbons prepared from Kevlar interacted much more strongly with C02 than rayon-based chars. Thus, the latter showed very little ability to separate air and C02, in marked contrast to the Kevlar-derived materials. 

Various organic wastes were carbonized with super-heated water vapor using a rotary drum super-heated water vapor generator (SJH-IOM, Johnson Boiler, Japan) and a rotary kiln (JBT-1OM, Johnson Boiler, Japan). The organic wastes were processed at 623 K for 30 - 90 min. Process data and properties of various carbonized materials are summarized in Table 1. An activated carbon (Granular Shirasagi GS3 x 4/6, Takeda Chemical Industries Ltd., Japan) and an activated carbon prepared for alkaline gas adsorption (GAH 4-8, Cataler Corp., Japan) were used as controls. 

ADSORPTION OF METHYLENE BLUE FROM WATER ONTO ACTIVATED CARBON PREPARED FROM COIR PITH,... 

C. Namasivayam and D. Kavitha, Removal of Congo red from water by adsorption onto activated carbon prepared from coir pith, an agricultural solid waste. Dyes Pigments, 54,47-58,2002. 

Yoshizawa, N., Yamada, Y., Furuta, Y., Shiraishi, M., Kojima, S., Tamai, H. and Yasuda, H., Coal-based activated carbons prepared with organometallics and their mesoporous structure. Energy Fuels 11 (1997) pp.327-330. 

Jia Guo and Aik Chong-Lua, Effect of sur ce chemistry on gas -phase adsorption by activated carbon prepared from oil-palm stone with pre-impregnation . Separation and Purfication Technology 18 (2000) 47-55. 

Lee Y. W., Park J. W., Choung J. H., and Choi D. K., Adsorption characteristics of SO2 on activated carbon prepared from coconut Shell with potassium hydroxide activation, Environ. Sci. Technol. 36 (2002) pp. 1086-1092. 

Pastor-Villegas J, Duran-Valle CJ (2002) Pore structure of activated carbons prepared by carbon dioxide and steam activation at different temperatures from extracted rockrose. Carbon 40(3) 397 02... 

TABLE 16 Uptakes of Substituted Phenols, Expressed as Normalized Surface Areas (with Respect to Phenol) as a Eunction of the Degree of Bum-Off (BO) for Activated Carbon Prepared from Olive Stones... 

Gonzalez J.C.,.Gonzalez M.T, Molina-Sabio M. Rodriguez-Reinoso F. (1995) Porosity of activated carbons prepared from different lignocellulosic materials. Carbon, 33,1175,... 

ADSORPTION OF HUMIC SUBSTANCES ON ACTIVATED CARBON PREPARED FROM LOCALLY AVAILABLE WASTE MATERIALS... 

While cassava is an important crop across a wide range of tropical environment, cassava peels are an agricultural waste from the foodprocessing industry. Activated carbon prepared from cassava peel was used as an adsorbent in removal of dyes and metal ions from aqueous solutions. The material impregnated with H3PO4 showed higher efficiency than the heat-treated material (Rajeshvarisivaraj et ah, 2001). 

Namasivayam, C. and Kadirvelu, K. (1997). Activated carbons prepared from coir pith by physical and chemical activation methods. Bioresour. Technol. 62,123-127. 

Several activated carbons prepared by carbonization in N2 at different temperatures (from 700 to 1300°C) have been used in a study on the adsorption of hydrocarbons by IGC [28]. For linear hydrocarbons the expected relationship between Vs and the number of carbon atoms is obtained. 

Giles, C.H. and Nakhwa, S.N. (1962). Adsorption XVI The measurement of specific surface areas of finely divided solids by solution adsorption. J. Appl. Chem., 12, 266-73. Lopez-Gonzalez, J., de, D., Valenzuela-Calahorro, C., et al. (1988). Adsorption of p-nitrophenol by active carbons prepared from obve wood. An. Quim., 84B, 47—51. Femandez-Cobnas, J., Denoyel, R., and Rouquerol, J. (1991). Characterization of activated charcoals by adsorption from solution. Stud. Surf. Sci. Catal., 62, 399—408. Somasundaran, P. and Fuerstenau, D.W. (1966). Mechanisms of alkyl sulfonate adsorption at the alumina-water interface. J. Phys. Chem., 70, 90-6. 

Oark, B.-J., Park, S-J., and Ryu, S-K. Removal of NO over copper supported on activated carbon prepared by electroless plating. J. Colloid Interface Sci., 217, 142-5. 

Table 23.2 Porosity parameters of potassium hydroxide (KOH) activated carbons prepared from various precursors and their capacitance values estimated by galvanostatic discharge in 3 imol/L H SO solution. The precursors are coal, coal semicoke, pitch mesophase, pitch semicoke, and a commercial activated carbon for A-C, A-CS, A-PM, and A-PS, A-AC, respectively (Adapted from Ref. [84].)...

Some mention should be made of a pseudo-activated carbon prepared by treating wood, peat, molasses, and similar materials with concentrated sulfuric or phosphoric acid, and heating to 120° to 300° C.69,70 The pseudo-carbon residue, after being washed with water, has adsorptive and ionic-exchange properties. These pseudocarbons should be used in their original wet state because drying causes a loss of adsorptive power. 

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